Deep Cleaning Records With Steam?

I have cleaned my records several times (3-4) with AIVS 3 step with a steam after each process and my records are very clean and sound great. However i still get a white powdery buildup on the stylus after playing one side of some records.Looking at the record under a microscope i can see what looks like a crystal like substance in a few of the grooves .
Does anyone know what this is or how to remove it? Steaming doesn't seem to remove this buildup.
Todd

Thanks CREM1 but this deposit is present before the very first cleaning. I have checked it under a microscope before it is cleaned and i can see it in the groove.I have been told it is mold release products from the record pressing or paper deposits from the record sleeve or deposits from the steaming. Could be mold release but not build up from the record sleeves cause i just checked and i have plastic lined record sleeves.After 6 cleanings and steamings the deposit has decreased by about 50% , i was hoping i could find a faster and cheaper way to remove this buildup.I am using up a lot of my cleaning solution.
Also i have been using distilled water in my steamer and rinse it out after every second steam and i have cleaned it with a descaler product i use in my water distiller, i think if it is safe enough for drinking water it should be safe enough for cleaning my records.

Crem1 - I have been using AIVS cleaning solution and it works great. However this super tough crystal like deposit in the grooves are very stubborn. I have found them to only be on Sheffield lab albums and after 6 cleanings with a total soaking time of 3 hrs i have only removed about 50% of the deposits. I am just using up large amounts of cleaning solutions for very little gain. I am just looking for something that might remove it in one shot even if it has to soak for a few hours. I will try soaking with the AIVS enzyme cleaner for 3 hrs straight and see what results i get. Also i am concerned i might be damaging the lp playing it with these deposits still on the lp since a white powdery substance is coming off it might be scratching the grooves. Or worse yet damage my $2k cartridge. I hope all the steaming i have been doing is not setting the deposits more firmly in the grooves. Only time will tell.

I talked with Mr Pendleton and he was very helpful .I will see if i can contact LAST and try find a way to remove these deposits.
Also i have found that if i steam my lp before playing it instead of using a carbon fiber record brush the static is much lower and the record sounds better.

I hope i don't have to wait 24hrs after steaming to play , i lightly steam my lp before every play to remove fine dust particles and reduce static.